This invention relates to the production of atomized metal powder and more particularly to improved apparatus for the production of atomized metal powder in a safer and more efficient manner.
The production of atomized powder of metals, such as aluminum, magnesium and the like, carries with it the attendant risk of explosion.
Conventionally, therefore, atomized metal powder is produced using a containment or chilling chamber into which the atomized metal stream is injected through an open end of the chamber positioned adjacent the atomizer and a liquid metal reservoir, the atomized metal stream being cooled or chilled with air introduced through the open end by a downstream exhaust fan. Such a system can result in safety hazards because any explosion occurring in the system can propagate backwards to the open-ended chiller chamber, often exposing operating personnel to hazardous conditions. Furthermore, the release of resultant burning aluminum particles with intense heat radiation through the open end of the containment vessel upon occurrence of an explosion can also result in further safety hazards.
While the use of a closed atomizing apparatus using a vertical updraft chiller chamber has certain advantages, it would be desirable to control the molten metal pressure to the atomizing nozzle to compensate for variations in chamber pressure, thereby affording greater control of particle size. This is particularly true when the system is designed to operate above atmospheric pressure using a "pushing" system with a blower to push the sweeping gas into the system as opposed to operating below atmospheric pressure using an eductor exhaust system, e.g., eductor, to pull the sweeping gas into the system.
The present invention solves these various problems in the prior art by providing a system which will permit adjustment of molten metal pressure and will also contain the gases and burning particles should an explosion occur.